feat(push): relay notifications as encrypted web push (#2906)

fluxer_admin/tests/api_deserialization.rs

@@ -418,6 +418,14 @@ fn deserialize_instance_config_response_with_unknown_keys() {
             "future_delivery_knob": 9,
             "excluded_user_ids": []
         },
+        "push_service_delivery": {
+            "enabled": true,
+            "config_version": 3,
+            "rollout_basis_points": 5000,
+            "rollout_salt": "push-service-delivery-v1",
+            "included_user_ids": ["1500000000000000002"],
+            "excluded_user_ids": []
+        },
         "experiment_delivery": {"poll_interval_seconds": 300, "poll_jitter_percent": 15},
         "registration": {
             "mode": "open",

fluxer_admin/tests/htmx_acceptance.rs

@@ -817,6 +817,9 @@ async fn spawn_mock_api() -> String {
 
 async fn mock_api(method: Method, uri: Uri) -> Response {
     let path = uri.path().to_owned();
+    if method == Method::PATCH && path == "/admin/instance/config" {
+        return json_response(instance_config());
+    }
     match (method, path.as_str()) {
         (Method::GET, "/admin/users/@me") => json_response(json!({ "user": admin_user() })),
         (Method::GET, "/admin/api-keys") => json_response(json!([])),